5D mark II drops frames when recording video
Posted by: Sulka
I've been meaning to write about the 5D mark II (which I've had for about 1.5 months now) for a while but given the amount of information in the web already, it's seemed somewhat pointless. However I have to rant a bit now, given the video mode on the camera was detected to have yet another fault. It drops frames, resulting in jerky movement.
Here's how the video mode in 5DmII works: the camera is in full auto mode while shooting video. The user can compensate the exposure to under- or overexpose, but you can't change the frame exposure time, aperture or sensitivity. (You can sort of work around this by fiddling the exposure compensation and pointing the camera here and there + locking exposure, but that workaround is not a real solution.) For some reason, the camera seems to sometimes make rational choices on the exposure, and sometimes prefer to use extremely high sensitivities even in bright light, resulting in noise.
Now, I noticed the video from the camera occasionally jerks a bit, but assumed it was my computer occasionally dropping frames due to the fact the 1080P footage from the camera is extremely CPU intensive to decompress. Turns out this is not a playback problem, but a fault in the camera. What's happening is, whenever you're recording video, if the camera changes the aperture, it skips 2-3 frames, and replaces those skipped frames in video stream with copies of the last frame recorded.
Reproducing this is very simple. If you have a variable aperture zoom lens, just change zoom in and out during capture of a moving subject, and check the footage frame by frame. For constant aperture lenses, find a spot that has dark and brightly lit spots that are bright enough that the camera has to change aperture when shooting (hint, point the camera out the window, then back in), record a clip while alternating pointing the camera to these spots, and check the footage. You can see the aperture being used during the video capture by depressing the shutter button halfway down. On my footage, I'm consistently getting four duplicated frames in a row when the aperture changes, making these clips useless.
The workaround is to always remember to lock the exposure with the * button prior to starting to record video.
With this issue in mind, I have a couple questions in mind. What's the point of having the camera work in forced full auto mode by default, if that mode produces jerky video footage? Why on earth can't I select the aperture manually, especially if the manual selection would prevent this from happening? Can a camera even be marketed to record video, if the camera regularly drops frames?
The most infuriating part about this that Canon still uses an old world communication policy, whereby they effectively don't talk to their customers. The web is chock full of angry commentary about all the issues and lack of features on the video capture, and there's no word whatsoever from Canon on whether anything related to the video will actually be changed.
Until this issue is fixed and the manual controls on the video are released as a software upgrade to the camera, I have to recommend anyone considering to use the camera to record video forgets about it. Sad, really.
Here's how the video mode in 5DmII works: the camera is in full auto mode while shooting video. The user can compensate the exposure to under- or overexpose, but you can't change the frame exposure time, aperture or sensitivity. (You can sort of work around this by fiddling the exposure compensation and pointing the camera here and there + locking exposure, but that workaround is not a real solution.) For some reason, the camera seems to sometimes make rational choices on the exposure, and sometimes prefer to use extremely high sensitivities even in bright light, resulting in noise.
Now, I noticed the video from the camera occasionally jerks a bit, but assumed it was my computer occasionally dropping frames due to the fact the 1080P footage from the camera is extremely CPU intensive to decompress. Turns out this is not a playback problem, but a fault in the camera. What's happening is, whenever you're recording video, if the camera changes the aperture, it skips 2-3 frames, and replaces those skipped frames in video stream with copies of the last frame recorded.
Reproducing this is very simple. If you have a variable aperture zoom lens, just change zoom in and out during capture of a moving subject, and check the footage frame by frame. For constant aperture lenses, find a spot that has dark and brightly lit spots that are bright enough that the camera has to change aperture when shooting (hint, point the camera out the window, then back in), record a clip while alternating pointing the camera to these spots, and check the footage. You can see the aperture being used during the video capture by depressing the shutter button halfway down. On my footage, I'm consistently getting four duplicated frames in a row when the aperture changes, making these clips useless.
The workaround is to always remember to lock the exposure with the * button prior to starting to record video.
With this issue in mind, I have a couple questions in mind. What's the point of having the camera work in forced full auto mode by default, if that mode produces jerky video footage? Why on earth can't I select the aperture manually, especially if the manual selection would prevent this from happening? Can a camera even be marketed to record video, if the camera regularly drops frames?
The most infuriating part about this that Canon still uses an old world communication policy, whereby they effectively don't talk to their customers. The web is chock full of angry commentary about all the issues and lack of features on the video capture, and there's no word whatsoever from Canon on whether anything related to the video will actually be changed.
Until this issue is fixed and the manual controls on the video are released as a software upgrade to the camera, I have to recommend anyone considering to use the camera to record video forgets about it. Sad, really.